Could I be pregnant??

Im on the pill, have been for about 5 years, I try to take them regularly but most days I take them at slightly different times.I had my period from Wednesday 11th May to Monday 16th May, then i missed my pills on Friday 21st and Saturday 22nd, i took 2 pills Sunday 23rd and 2 pills Monday 24th I had unprotected sex Wednesday 18th, Friday 21st and Saturday 22nd, (during the time that i missed pills). Since missing the pills I have been feeling slight stomach cramps (similar to period pain)!